In the field of plastics, it has become desirable to produce internally subdivided tubular bodies and the like. One application in industry would be that of providing reinforcing tubing that will withstand loads and heavy duty work. Another application is that of providing several inner conduits for housing electrical wires, pumping diverse fluids therethrough, etc. Manufacturing of such types of tubing has not been possible given the present state of the art in nozzles. In this regard, Kojimoto et al's U.S. Pat. No. 4,113,841 discloses a method for producing a preferably thermoplastic tubular body longitudinally partitioned by a diaphragm into two conduits.
This method does not precede the invention being disclosed herein, since Kojimoto's tubular body is partitioned by a separate strip to form said diaphragm. Also my invention relates to continuous and uninterrupted inner conduits which maintain the same proportion to one another throughout the complete extrusion of the pipe.